用方框中所词组的正确形式填空。每词只用一次。
laugh,     tooth,     little,   serious,     minute
【小题1】Lisa is _______ of us. She hardly ever smiles.
【小题2】The bus ride usually takes us about 25_____ to get to school?
【小题3】My baby brother has three _______ . He is too young to eat anything.
【小题4】We must try to eat_______ meat. Too much meat is bad for our health.
【小题5】He is very funny. He always makes his classmates _____.